JEE Main 2022 · 25 July · evening · Single correct · +4 / −1
The total number of acidic oxides from the following list is
NO, N₂O, B₂O₃, N₂O₅, CO, SO₃, P₄O₁₀
- (a) 3
- (b) 4
- (c) 5
- (d) 6
Answer and solution
Answer (b) 4
Solution
Chemistry ma’am · 2 steps
Most non-metal oxides are acidic, but CO, NO and N₂O are the neutral ones to strike off.
- Acidic oxide test. An acidic oxide reacts with water to give an acid, or reacts with a base to give a salt. A neutral oxide does neither. These are usually low-oxidation-state oxides like CO (C at +2), NO (N at +2) and N₂O (N at +1).
Oxide With water Nature NO no acid formed neutral N₂O no acid formed neutral CO no acid formed neutral B₂O₃ H₃BO₃, boric acid acidic N₂O₅ HNO₃ acidic SO₃ H₂SO₄ acidic P₄O₁₀ H₃PO₄ acidic - So. The acidic oxides are B₂O₃, N₂O₅, SO₃ and P₄O₁₀. That makes 4, option (b).
The idea to keep. Memorise the neutral oxides: CO, NO and N₂O. Apart from these, the higher oxides of non-metals and metalloids are acidic.
Answer from the NTA final answer key. Solution by PrepWiser.